Quercetin induces p53-independent cancer cell death through lysosome activation by the transcription factor EB and Reactive Oxygen Species-dependent ferroptosis
Quercetin induces p53-independent cancer cell death through lysosome activation by the transcription factor EB and Reactive Oxygen Species-dependent ferroptosis
复制标题
槲皮素通过 TFEB 介导的溶酶体激活和 ROS 依赖性铁死亡诱导 p53 独立的癌细胞死亡
DOI：
10.1111/bph.15350
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发表时间：
2021-02-02
影响因子：
7.3
通讯作者：
Zhou, Jing
中科院分区：
文献类型：
--
作者：
Wang, Zi-Xuan;Ma, Jing;Zhou, Jing
背景和目的：与正常细胞相比，癌细胞表现出对铁的更多依赖性，并且对铁依赖性程序性细胞死亡（铁死亡）的敏感性增强。槲皮素具有抗癌作用，但其潜在的分子机制尚不清楚。在本研究中，我们旨在探讨溶酶体功能和铁死亡在槲皮素抗癌潜力中的作用。实验方法：我们使用MTT测定和DNA含量分析来评估细胞毒性，集落形成测定来研究细胞增殖，并使用流式细胞术和共聚焦显微镜来检测溶酶体酸化和蛋白酶活性。使用蛋白质印迹、细胞亚分级、RT-PCR 和 siRNA 转染来建立分子作用机制。主要结果：已知槲皮素可促进各种癌细胞系中不依赖于 p53 的细胞死亡。尽管槲皮素可诱导自噬，但 Atg7 的基因沉默无法影响槲皮素诱导的细胞死亡。相比之下，溶酶体抑制剂和转录因子 EB 的敲低都可以阻止槲皮素诱导的细胞死亡，表明溶酶体的参与。接下来，发现槲皮素通过 EB 的核转位和溶酶体基因的转录激活依次诱导溶酶体激活。值得注意的是，槲皮素促进溶酶体依赖性铁蛋白降解和游离铁释放。这种作用和槲皮素诱导的 ROS 产生协同作用，导致脂质过氧化和铁死亡。此外，Bid可能将铁死亡与细胞凋亡联系起来，导致细胞死亡。结论和启示：槲皮素诱导EB介导的溶酶体激活和增加铁蛋白降解，导致铁死亡和Bid相关的细胞凋亡。这项研究的结果可能会扩大我们目前对槲皮素作为抗癌剂机制的了解。
Background and Purpose: Cancer cells exhibit more dependence on iron and enhanced sensitivity to iron-dependent, programmed cell death (ferroptosis) than normal cells. Quercetin exerts anti-cancer effects, but the underlying molecular mechanism is largely unknown. In this study, we aimed to investigate the involvement of lysosome function and ferroptosis in the anti-cancer potential of quercetin.Experimental Approach: We used MTT assays and DNA content analysis to evaluate the cytotoxicity, colony formation assay to investigate cell proliferation, and flow cytometry and confocal microscopy to detect lysosomal acidification and protease enzyme activity. Western blotting, cell subfractionation, RT-PCR and siRNA transfection were used to establish molecular mechanisms of action.Key Results: Quercetin is known to promote p53-independent cell death in various cancer cell lines. Although quercetin induces autophagy, genetic silencing of Atg7 fails to affect quercetin-induced cell death. In contrast, both lysosome inhibitors and knockdown of the transcription factor EB can prevent quercetin-induced cell death, suggesting the involvement of lysosome. Next, quercetin is found to induce lysosomal activation sequentially through nuclear translocation of EB and transcriptional activation of lysosomal genes. Notably, quercetin promoted lysosome-dependent ferritin degradation and free iron release. This action and quercetin-induced ROS generation synergistically resulted in lipid peroxidation and ferroptosis. Furthermore, Bid may link ferroptosis with apoptosis to cause cell death.Conclusion and Implications: Quercetin induced EB-mediated lysosome activation and increased ferritin degradation leading to ferroptosis and Bid-involved apoptosis. Results from this study may expand our current knowledge about the mechanism of quercetin as an anti-cancer agent.